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Supreme Court Says EPA Can Regulate Greenhouse Gas Emissions

In the latest decision on the U.S. Environmental Protection Agency’s (EPA) authority to regulate carbon pollution, the U.S. Supreme Court reaffirmed EPA’s authority to regulate greenhouse gas emissions under the Clean Air Act, but voted 5-4 to limit permitting requirements. The ruling does not directly affect the EPA’s latest proposed rule to reduce greenhouse gas emissions from existing power plants, and generally reaffirmed the EPA’s authority to regulate greenhouse gases under the Clean Air Act.

The court narrowly defined the question to decide in the case, limiting its review to the EPA’s authority to require permits for greenhouse gas emissions from new and modified sources. EPA interpreted the Clean Air Act to require permits for all such sources of greenhouse gas emissions, but initially limited permitting requirements to large sources out of administrative necessity. Justice Antonin Scalia, writing for the majority, concluded that the Clean Air Act does not permit EPA’s interpretation—the EPA cannot opt only to regulate the large sources because it is easier. But Justice Scalia read the Clean Air Act differently from the EPA in a way that arrived at a similar end point. According to the court, greenhouse gas emissions do not trigger permitting requirements, but the EPA can require sources to minimize greenhouse gas pollution when they are required to obtain permits for other pollutants. Because almost all new and modified large sources could trigger permitting requirements via emissions of traditional pollutants, the court’s decision left the EPA largely with what it desired—the authority to forego enforcement against small sources but permit greenhouse gas emissions from large sources.

“It bears mention that EPA is getting almost everything it wanted in this case,” said Scalia. “It sought to regulate sources that it said were responsible for 86 percent of all the greenhouse gases emitted from stationary sources nationwide. Under our holdings, EPA will be able to regulate sources responsible for 83 percent of those emissions.”

The ruling follows another decision this spring that upheld the EPA’s authority to regulate air pollution that crosses state borders.

Satellite to Study Key Greenhouse Gas

On Wednesday the National Aeronautics and Space Administration (NASA) satellite designed to track atmospheric carbon successfully launchedThe Orbiting Carbon Observatory-2, twin to the original failed 2009 satellite, will study how oceans, soils and forests absorb carbon dioxide.

“Knowing what parts of Earth are helping to remove carbon from our atmosphere will help us understand whether they can keep doing so in the future,” said Michael Gunson of NASA’s Jet Propulsion Laboratory. “Quantifying these sinks now will help us predict how fast CO2 will build up in the future.”

Carbon dioxide exists in the atmosphere in trace amounts: 400 parts per million. Cars and factories are adding 40 billion tons of the gas per year. The satellite will spend at least two years examining carbon dioxide from 438 miles above the Earth’s surface. According to NASA, the satellite will produce the “most detailed picture to date of natural sources of carbon dioxide.” NASA will use this data to study how these sources and sinks are distributed and change over time.

Methane Leaks, Bans Related to Fracking

A New York Appeals Court voted 5-2 on Monday to uphold bans on hydraulic fracturing, or “fracking,” in two upstate New York towns. The ruling affirmed a lower-court decision that state oil and gas laws do not preempt town ordinances.

“The towns both studied the issue and acted within their home rule powers in determining that gas drilling would permanently alter and adversely affect the deliberately-cultivated, small-town character of their communities,”  the Appeals Court ruling concluded.

The state is still waiting on a health impact review before lifting its own 6-year-old moratorium on fracking.

In Pennsylvania, gas wells—especially newer and unconventional wells—are leaking methane, according to a study in the Proceedings of the National Academy of Sciences. Using data from more than 75,000 state inspections of wells conducted from 2000 to 2012, researchers found newer traditional wells drilled after 2009 had a leak rate of about 2 percent; rising to about 6 percent with unconventional wells. By comparison, older wells drilled before 2009 had a leak rate of about 1 percent.

For Rob Jackson, who has studied methane leakage at Duke University, the basic conclusions hold. “Hydraulically fractured shale wells appear to have more problems than conventional wells,” Jackson said. “If so, it’s probably because the wells are longer, must bend to go horizontal and take more water and pressure than in the past. The combination makes well integrity a challenge.”

Industry officials like Marcellus Shale Coalition Spokesman Travis Windle aren’t in agreement with the study’s findings, calling the conclusions a “clear pattern of playing fast and loose with the facts.”

The Climate Post offers a rundown of the week in climate and energy news. It is produced each Thursday by Duke University’s Nicholas Institute for Environmental Policy Solutions.